So a customer came in with lean codes that an independent highly regarded Jaguar specialist could not solve. High long term fuel trims
P0171 and P0174 plus occasional Maf codes. The shop tried a set of aftermarket Denso compatible MAF units first, after that didn't work they tried OEM from Jaguar dealer MAF sensors, those did not seem to work either. Customer asked me for advice. After running diagnostics on his vehicle I told him that mass airflow sensors are very highly suspect, and told him to go back to the Jaguar specialist to double check everything. So one more time they tackled the problem and managed somewhat to mask it by installing non supercharged MAF units. I checked the vehicle over again, and suspicion I decided to take a look at what's going on. This is what I found,,, lol for anyone that's familiar with this picture, this highly regarded independent Jaguar specialist managed to install airflow director screen backwards, not just once but three times with MAF replacements .. WTF ,😂. Customer was also told that his air filters look brand new 😂. Look at the photo
Fixed the screen installation put new air filters and all issues resolved. . Customer



​​​is ecstatic 3 months long saga is over, especially after loading the long-awaited ECU tune.

 

I knew those dam things were a problem! Mine were installed off-center. But there's no way to correct it - unless they make a right and left handed one.

If I ever see my P0101 code again I am going to just remove those screens altogether.

Good work.

 

There is no way to install them incorrectly if you follow the groves and match the slots . They won't be perfectly centered but they will be where they are soposed to be for correct MAF reading

 

Nice result

 

Love the quote 'Highly regarded Jaguar Specialist'. Wrong MAFs?? Installed backwards?? and those filters!!... Jeepers.
Related: A friend once had all kinds of issues as the MAFs were covered in filter oil... done at a speedshop.
Fixed in my driveway. After I made him clean his air feed system (with dish detergent, rinsed in vinegar water) he convinced himself to go back to paper filters.

So tell me, how much money and time did they save by not just going to the proper service department in the first place. Or is this customer's time not worth money?

Thanks for sharing @AlexJag !

 

I don't believe in k/n filters myself, oil plus extra dust not worth it, good job on the fix!
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​​​​As far as the customer going to the right place , I can't really blame him as the shop was highly regarded until this. I think Jaguar dealer would have been a lot more responsible or at least I would hope so.